A U.S. Air Force MH-53 Pave Low helicopter sits on the tarmac. A U.S. Air Force MH-53 Pave Low helicopter from the 20th Expeditionary Special Operations Squadron sits on the tarmac prior to a final combat mission at Joint Base Balad, Iraq, on Sept. 27, 2008. The Pave Low is being retired after nearly forty years of service to the Air Force. SHARE: Download: Full Size (0.05 MB) Credit: VIRIN: 979346-T-LOK60-819.jpg Photo Gallery